The Subversion server provides access to the source code for PLT
software (DrScheme, MzScheme, etc.) as it is being developed. The
server is useful for those who want access to the latest and greatest
version of PLT software, either to take advantage of new features or to
help test the new code.

The simplest way is to just point your browser at this URL, and
view the repository.

If your operating system has the capability to mount "web
folders", you can mount this URL, and get the repository as a
plain directory.

For more detailed information, you can use the
ViewVC interface to the repository.

Finally, using the
Subversion client,
you can checkout the repository with the following command:

svn checkout http://svn.plt-scheme.org/plt/trunk plt

(Make sure that you use "trunk", or you will get many
copies of the whole tree.)

Repository Overview

The PLT trunk contains the following directories:

collects: Scheme code, organized into collections

man: Unix man pages

src: C code

mac: Mac code

mred: MrEd code

worksp: Windows MSVC makefiles and projects

starter: Windows program-launcher code

srpersist: SrPersist code

mysterx: Windows MysterX code

mzscheme: MzScheme code

wxxt: X MrEd code

wxwindow: Windows MrEd code

wxmac: Mac MrEd code

wxcommon: MrEd code

Of course, when building under Windows (for example), the directories
for Unix and Mac aren’t needed. Similarly, the MrEd or MysterX
directories are not needed to build only MzScheme.

Building and Using the Code

Building C Source

Compilation information is provided by README files in various
plt/src directories. Start with plt/src/README.

Downloading Pre-Release Binaries

If a binary for your platform is available from
the pre-release binaries page, then
you can download the binaries instead of building them. The pre-release
binaries are updated nightly by building with the trunk code.

For installation instructions, see the bottom of the pre-release
download page for your platform.

Updating Collection Files

After building and/or installing the binaries, byte-code-compile the
Scheme sources by running Setup PLT (setup-plt in Unix). Whenever
you update Scheme code in the plt/collects directory, run Setup
PLT.

Change Logs

The change logs can be found in HISTORY files within
plt/notes. For example, plt/notes/mzscheme/HISTORY records
the changes made to MzScheme. Relatively detailed notes are kept
between regular releases, but then collapsed when the release occurs.

The version numbers for MzScheme and MrEd are always kept in sync. A
pre-release version number has the form N.M.P.Q, where N.M.P is usually
the version number for the previous regular release, and Q indicates the Qth
trunk version after the N.M.P release. For example, 4.2.0.8 means
"the 8th checkpoint after the release of version 4.2.0".

The Scheme code implementing DrScheme evolves at its own pace, but does
not have a version number, per se. Instead, it uses the date of the
checked out source for a reference.

Old Sources

PLT Scheme used to be hosted on CVS, but has moved to Subversion. The
new repository does not contain the complete history, so the CVS
repository is still active for historical content.